European Inventor Award

Lighting up the code of life

Winner of the European Inventor Award 2013 in the category SMEs

Pål
Nyrén, inventor of Pyrosequencing

The spiral-staircase-shaped
double helix of DNA contains the genetic information to all biological life on
earth. Genetics, or the study of genes, is leading to improved medical research
and treatment. It is also revolutionising our understanding of biology,
evolution and ultimately, of ourselves.

As the inventor of
important DNA sequencing technology, Swedish scientist Pål Nyrén has been
instrumental in furthering genetic research, making it more efficient and
affordable, and its use more widespread. His patented sequencing method, known
as Pyrosequencing, is one of the most common methods used today.

Early inspiration

As a post-doctoral student at the University of Cambridge, Pål
Nyrén often found himself frustrated by the time-consuming and complex task of
manually performing DNA sequencing. He was using the so-called Sanger method,
named after Nobel Prize laureate Frederick Sanger, who had pioneered it over a
decade earlier. The method remains in use today - albeit improved and
automated - but in the mid-1980s it was still a rather gruelling task.

Sitting beneath a figurative Newton's apple tree - in this case cycling home
from the lab on a dark, rainy evening in January 1986 - Nyrén first envisioned
a new method of sequencing DNA.

As a PhD student at Stockholm University, Nyrén researched in the
field of photosynthesis and developed a method capable of capturing the light
emissions of a chemical reaction. Drawing on this experience, Nyrén's epiphany
concerned transferring this method of measurement into the process of DNA
sequencing.

Pyrosequencing’ is named for the ‘fiery’ luminescence produced during the process – similar to the luminescence a firefly displays at night.

Keeping the faith

After completing his post-doctoral work, Nyrén returned to Sweden and
unsuccessfully tried to obtain financing to bring this new sequencing method to
life. According to Nyrén, the grant-giving body did not, at the time, fully
realise the importance of the method he was proposing.

Despite the apparent setback, he continued to work on the sequencing technique,
often spending his evenings and weekends on its development. However, it wasn't
until 1994 when he was fully able to dedicate himself to the task.

Aided by colleagues at the Royal Institute of Technology (KTH) in
Stockholm, Nyrén finally had the time and resources necessary to develop and
test his novel DNA sequencing method. He and his colleagues Mathias Uhlen and
Mostafa Ronaghi filed an initial patent for a "Method of sequencing DNA", which
was granted in 2001.

Shine a light

Unlike the existing DNA-sequencing procedures at the time, Nyrén's
Pyrosequencing method did not resort to radioactive labelling. This technique
forces scientists to handle potentially dangerous radioactive material. Nyrén's
invention also allowed for much easier and faster sequencing.

‘Pyrosequencing' is named for the ‘fiery' luminescence produced during the
process - similar to the luminescence a firefly displays at night. As the DNA
is sequenced, a chemical reaction produces light signals that are captured by
sensitive cameras, which help determine the sequence of bases in the DNA.

The Pyrosequencing method was first sold by the company founded by
Nyrén, Uhlen and Ronaghi - Pyrosequencing AB - in 1999. It quickly established
itself as one of the most common methods of so-called ‘next-generation
sequencing', which describes technologies that help generate read-outs of DNA
sequences at much greater speeds and volumes. The results have been impressive:
Since 2003, the speed of sequencing a whole genome has more than doubled every
two years.

“Our technological advantage, the market and our strong patent portfolio were decisive for the acquisition.”

Start-up success

In 2003, the successful start-up Pyrosequencing AB changed its
name to Biotage. Five years later it was acquired for $53 million by Qiagen, a
provider of sample and assay technologies. "Our technological advantage, the
market and our strong patent portfolio were decisive for the acquisition,"
recalls Nyrén.

The Pyrosequencing method was also licensed to 454 Life Sciences,
now owned by the pharmaceuticals giant Roche. The method was used to develop an
array-based platform for sequencing, greatly increasing the speed and volume at
which DNA can be sequenced.

Growing markets and
sequencing speeds

Incidentally, it was a 454-machine that sequenced the genome of
James Watson, who - along with fellow molecular biologist Francis Crick - had
discovered the double-helix structure of DNA in 1953. Watson's genome was
sequenced in just two months in 2007 - compared to the 13 years that it took to
sequence the first ever human genome completed in 2003.

The sequencing instrument market currently generates annual revenues
of around $1.6 billion, and it is expected to grow to $2.2 billion within the
next four years. Due to the steep price of the individual testing units, sales
of next-generation sequencing instruments are largely restricted to developed
countries.

Europe accounts for just over a third of the overall market.
However, increasingly affordable prices will undoubtedly make DNA sequencing
accessible to a wider population.

Decreasing costs,
increasing knowledge

Continued demand, improved sequencing methods and related
technological advances have been driving down the cost of DNA sequencing. The
cost of sequencing a genome in September 2001 was estimated at $95,263,072
whereas the cost has fallen to around $7,743 per genome in October of 2011.

This trend has contributed to a veritable revolution in the field of genetics.
The greater access to, and the affordability of DNA sequencing, has spawned the
creation of new fields of study. It also affords us the possibility to examine
the building blocks of life in ever-closer detail. Investigating genes and
their interactions help us understand hereditary diseases and feeds into research
for treating them.

“The main problem is to get the research / the invention to bigger companies; Pyrosequencing AB succeeded in attracting the attention from a big player (Qiagen) and to realize the breakthrough of the technology.”

Genetic clues to fight
disease

For example, genetic analyses of cancer tumours are as different
from each other as one patient's genetic profile differs from the next. Cancer treatment that is effective for one
patient might not work on the ‘same' type of cancer in another.

The genetic specificity of the individual, as well as the disease,
suggests that for many illnesses, the most effective form of treatment is
individualised, or tailored to, the patient. This form of ‘personalised
medicine' will likely be the future of healthcare, and it relies heavily on
genetic knowledge gleaned from DNA sequencing.

Future improvements in human health, as well as other essential
applications - such as in criminal forensics - depend on continued genetic
research. This research, in turn, requires sequencing technology that can
process increasingly larger quantities of genetic material in shorter amounts
of time.

The method of Pyrosequencing, developed by Pål Nyrén and his team,
makes such vital genetic research possible and will not only contribute toward
our growing theoretical body of knowledge on genetics but could likely help in
combating life-threatening diseases such as cancer.

How it works

The method developed by Nyrén involves taking a single strand of
DNA and synthesising its complementary strand, one base pair at a time, with a
DNA-synthesising enzyme and a substrate containing a chemiluminescent enzyme -
an enzyme that is emitting light as the result of a chemical reaction.

Solutions of the four nucleotide bases adenine, guanine, cytosine
and thymine - are added sequentially. A successful pairing of a base pair
produces a light signal through the release of a chemiluminescent enzyme that
can be detected by a camera and mapped by software. The process is repeated for
each of the four different nucleotide solutions, and the mapped bases combined
to determine the entire DNA sequence.

A short history of DNA sequencing

The double-helix structure of DNA was discovered in 1953 by James
Watson and Francis Crick. 50 years later, the first human genome to be
sequenced was completed at tremendous cost over a period of thirteen years. In
the short time since that milestone was reached in 2003, the speed and cost of
sequencing a whole genome has changed tremendously. Today, a genome can be
sequenced in weeks and at a cost of $8000 - a far cry from the approximately
$95 million the first genome cost. Overall, the speed of sequencing a whole
genome has more than doubled every two years.